The bombing, which killed several other people, highlights an accelerating campaign targeting government officials, from mid-level civil servants to the highest echelons of the Syrian regime.

State television said Prime Minister Wael al-Halqi was not hurt in the bombing, which struck his convoy as it drove through the posh Mazzeh neighborhood — home to embassies, government officials and business elites with close ties to the regime. Footage of the scene broadcast on state TV showed the charred hulks of cars and the burnt-out shell of a bus in a street littered with rubble.

The attack on al-Halqi punctuated a series of attacks on government officials in recent weeks. On April 18, gunmen shot dead the head of public relations at the Ministry of Social Affairs while he dined at a Mazzeh restaurant. A day later, a Syrian army colonel was killed in Damascus, and five days after that a bomb killed an official from the Electricity Ministry.

Then there are the larger attacks that have shaken the regime to its core.

Last month, a suicide bombing at a Damascus mosque killed Sheik Mohammad Said Ramadan al-Buti, a leading Sunni Muslim preacher and outspoken supporter of Assad. That followed a blast last July that killed four top regime officials, including Assad’s brother-in-law and the defense minister, at the Syrian national security building in the capital.

Eager to assure the public that al-Halqi survived Monday’s attack, the state-run Al-Ikhbariya station said the prime minister attended a regular weekly meeting with an economic committee immediately after the bombing. The station broadcast video of al-Halqi sitting at a table with several other officials.

Later, in its evening news program, state TV showed video of al-Halqi denouncing the attack, calling it a “terrorist and criminal act” and wishing the wounded a speedy recovery.

A government official said two people were killed and 11 wounded in the blast, while the Britain-based Syrian Observatory for Human Rights activist group put the death toll at five, including two of al-Halqi’s bodyguards and one of the drivers in his convoy.

The government official spoke to The Associated Press on condition of anonymity because he was not authorized to give official statements to reporters.

The bombings and assassinations are part of the wider violence wracking Syria as the nation’s conflict enters its third year. The crisis began with largely peaceful anti-government protests in March 2011, but has since morphed into a civil war that has killed more than 70,000 people, according to the United Nations.

State TV quoted Syrian Information Minister Omran al-Zoubi as saying that targeting al-Halqi, who is in charge of carrying out a political program to end the nation’s crisis, shows that some in the opposition “reject a political solution.”

Al-Halqi, who was appointed prime minister in August after his predecessor defected, heads a ministerial committee charged with holding a dialogue with opposition groups. The initiative is part of efforts to implement a peace plan, including a national reconciliation conference, that Assad outlined in a speech in January.

The proposal, however, has never gotten off the ground. The political opposition abroad says it will not accept anything less than Assad’s departure, and roundly dismissed the president’s plan as a political ploy. The myriad rebels fighting on the ground — without a unified command — have also rejected talks with the government as long as Assad is in power.

There was no immediate claim of responsibility for Monday’s attack, but bombings like the one that struck the prime minister’s convoy have been a trademark of Islamic radicals fighting in the rebel ranks, such as the al-Qaida-linked Jabhat al-Nusra.

While the rebels have wrested much of northern Syria from the regime in the past year, the government hold on Damascus is firm and regime forces have been on the offensive recently in the capital’s suburbs and in the countryside near the border with Lebanon. In the northwest, regime troops recently opened up a key supply road to soldiers fighting in the embattled city of Aleppo.

As the regime has sought to shore up its strategic position, it has come under allegations of using chemical weapons on at least two occasions dating back to December.

The U.S. said last week that intelligence indicates the Syrian military has likely used sarin, a deadly nerve agent, echoing similar assessments from Israel, France and Britain. Syria’s rebels accuse the regime of firing chemical weapons on at least four occasions, while the government denies the charges and says opposition fighters have used chemical agents in a bid to frame it.

At the United Nations, Secretary-General Ban Ki-moon reiterated his appeal to Syria to allow a team of experts into the country “without delay and without any conditions” to investigate allegations of chemical weapons use. He added that he takes seriously a recent U.S. intelligence report which indicates Syria has twice used chemical weapons.

The Assad government has asked for a U.N. investigation, but wants it to be limited to an incident near Aleppo in March. Ban has pushed for a broader investigation, including a December incident in the central city of Homs.

A U.N. team of experts has already begun gathering and analyzing available evidence, but Ban said onsite activities are essential if the U.N. is to establish the facts and “clear all the doubts.”

Meanwhile, a new jihadi group calling itself the Ahrar al-Bekaa Brigades announced its formation and warned the pro-Syrian Lebanese militant Hezbollah group to stop intervening in the Syrian civil war or face attacks in Lebanon.

According to the SITE Intelligence Group, which tracks Islamist extremist messages, the statement was distributed on anti-Assad Facebook pages Sunday.

In the statement, the previously unheard of group claims that Hezbollah is acting on Iran’s orders to “slaughter” the Syrian people. It pledged to prevent Hezbollah’s intervention “with all means and ways, even if we have to move the fight to the inside of the Lebanese territory.”

The Shiite Muslim Hezbollah is known to be backing regime fighters in Shiite villages near the Lebanon border against the mostly Sunni rebels fighting to topple Assad. The Syrian opposition accuses Hezbollah of taking part in the Syrian military crackdown.